Conventionally, there is known an information communication system including a content delivery apparatus and a content output apparatus. The content delivery apparatus deliver content data. The content output apparatus can output contents represented by content data downloaded from the content delivery apparatus. Various techniques are proposed for such information communication system for protecting the copyright of content data and improving the convenience of content users.
For example, Patent Document 1 discloses the information communication system that allows a group of specific authorized users to use contents received or purchased via a communication link on terminals other than the reception terminal. This information communication system uses a card that stores a user identification number unique to the card and a group secrete key common to the group. A user inserts the card into a terminal that stores contents. The user further enters a password to use a content.
According to the construction disclosed in Patent Document 2, a user other than a vehicle owner saves music data in a music delivery server. The music data can be reproduced free of charge on a music reproduction apparatus mounted on the vehicle. When a user wishes music delivery on the music reproduction apparatus, he or she supplies his or her user ID to the music reproduction apparatus. After the authentication is confirmed between the music reproduction apparatus and a music delivery apparatus, the user requests to download music data to be delivered.
Patent Document 3 discloses the construction that enables users to enjoy purchased contents at various locations. Specifically, a recording medium records identification information that ensures the right to output contents. A user inserts the recording medium into a content output apparatus for outputting contents. The content output apparatus reads the identification information recorded on the recording medium. When the user has the right to output content data, he or she can download the content data to the content output apparatus from a sever apparatus.                Patent Document 1: JP-H7-297818 A        Patent Document 2: JP-2002-116769 A        Patent Document 3: JP-2004-62728 A        
According to the above-mentioned constructions, however, the user needs to perform operations for acquiring content data from a content delivery apparatus so as to output the purchased content to the content output apparatus that does not store the content data. The user feels it inconvenient to perform such operations consciously.